This axial (cross sectional) FLAIR (fluid attenuated inversion recovery) MRI of the brain demonstrates multiple focal areas of increased T2 signal within the white of both cerebral hemispheres in this person with lyme disease. Lyme disease is the most common tick borne disease in the northern hemisphere. This is caused by a form of bacteria called borrelia. The findings on brain MRI scans can be similar to multiple sclerosis or other more common causes of white matter disease.